Malignant tumors are the world's major public health issue and the second leading cause of morbidity in the United States. It is estimated in the American Cancer Society's Annual Cancer Report of 2017 that there will be 1,688,780 new cancer cases and 600,920 cancer deaths in the United States in 2017. It means that about 1,650 deaths occur daily. Moreover, the National Health Department, Taiwan Ministry of Health and Welfare released the latest list of the top ten cancers in May, 2017, showing that the number of patients with cancers and the rate of incidence grow increasingly in Taiwan, and malignant tumors have always been the first leading cause of morbidity for the consecutive 34 years. However, early diagnosis of cancers and proper early treatments of the patients can greatly improve the survival rate. For example, if patients with colorectal cancer and breast cancer are given appropriate treatment in the early stage of cancers, the prognosis of the patients is usually good.
The glucose analogue 18F-FDG (2-Deoxy-2-fluoro-D-glucose) commonly used in clinic at present suffers from many restrictions during the use. For example, 18F-FDG is difficult to be prepared, and the process requires the use of a cyclotron to produce F-18. However, such an apparatus is highly expensive, and not a usual basic apparatus equipped in a hospital. Moreover, a synthesis kit is necessitated during the preparation of 18F-FDG, and 18F-FDG can be obtained only after the steps of water removal, fluorination, deprotection, and others, so the synthesis time is long. Furthermore, 18F-FDG is absorbed in all the tissues or organs that metabolize glucose in an organism, resulting in a very high background value in the brain and heart. This makes it difficult to distinguish the normal tissue from the tumor using 18F-FDG imaging in these organs and their surrounding tissues, such that 18F-FDG has limitations in detection therewith. Moreover, the 18F-FDG uptake is also high in an inflammatory tissue, so the tumor is also difficult to be distinguished from the inflammatory tissue. It can be seen that the preparation of 18F-FDG is complex and time consuming, and the specificity is low. In view of this, there is an urgent need in the art for an improved multivalent saccharide complex, to overcome the defects existing in the prior art.